/*
 * @Description: typeof
 * @Author: rendc
 * @Date: 2022-09-26 11:35:50
 * @LastEditors: rendc
 * @LastEditTime: 2022-09-26 11:42:30
 */
console.log("undefined:" + typeof undefined);
var a;
console.log("a:" + typeof a);
var b = true;
console.log("b:" + typeof b);
let c = "123";
console.log("c:" + typeof c);
let d = 123;
console.log("d:" + typeof d);
let obj = {}
console.log("obj:" + typeof obj);
let arr = [1, 2, 3]
console.log("arr:" + typeof arr);
let obj1 = null
console.log("obj1:" + typeof obj1);
function add () {
  console.log("add");
}
console.log("add:" + typeof add);
